DESCRIPTION (adapted from the Abstract): The dramatic advances in HIV clinical care which have occurred recently will greatly benefit HIV-infected children as well as adults. However, the markedly increased efficacy of new and older antiretroviral agents used in combination is dependent on strict patient adherence to therapy. In this study the researchers will enroll and follow, for a 36-month period, 80 perinatally HIV-infected children who are beginning or receiving highly active antiretroviral therapy (HAART) with three agents. Adherence rate and patterns of poor adherence will be determined utilizing Medication Event Monitoring System (MEMS) Track Caps, a medication bottle cap containing microelectronics that record each time the bottle is opened. The Principal Investigator hypothesizes that adherence rate during an initial follow-up period will be predicted by caregiver and child determinants at baseline, measured with structured interview and standard psychological instruments. These include: severity of child's illness; medication history, duration of the current medication regimen; caregiver, child, and family demographics; caregiver HIV knowledge; complexity of the regimen; caregiver health beliefs; caregiver social support; parenting stress; caregiver psychiatric symptoms; and child distress. The Investigator hypothesizes, further, that changes in these baseline determinants over time will function as mediating factors and impact upon the adherence rate. These mediating factors will be measured periodically over the course of study. During the initial follow-up period, families will receive a "standard of care" outpatient multidisciplinary approach to optimize adherence involving nursing, social work, and mental health services. After six months of follow-up, a monthly peer health educator home visit intervention will be added designed to improve adherence rate over baseline by identifying barriers not apparent in the outpatient clinic setting, enhancing caregiver knowledge, and influencing other mediating factors. An intensive intervention will be added for families with repeated poor adherence after the addition of the home visit intervention. The intensive intervention will include weekly peer health educator home visits and individualized mental health services. Through correlation of adherence data with periodic viral plasma RNA quantitation obtained in the course of clinical care, the adherence rate necessary to maintain a clinically relevant antiviral effect will be defined. A biological repository will be established and maintained, so that future studies may define the alteration in medication adherence and patterns of alteration that lead to development of viral resistance.